Systematic review, meta-analysis and economic modelling of ...

DOI: 10.3310/hta17010 Health Technology Assessment 2013 Vol. 17 No. 1£27,546/QALY, so the 10-hour troponin strategy may be cost-effective for patients without known CAD if adecision can be made and the patient discharged as soon as the 10-hour troponin result is available.The effects of suboptimal diagnosis by the biomarkers were also estimated. The number of adverse events(reinfarctions and deaths) and their proportions for each of the biomarker strategies are shown in Table 46(population without known CAD) and Table 47 (population with known CAD). These tables show theeffect of different testing strategies on clinically relevant outcomes across the whole presenting population.However, clinicians and patients are often more interested to know the risk of adverse outcome in thosedischarged after negative testing. These estimates are given in Table 48 (population without known CAD)and Table 49 (population with known CAD). It should be recognised that the differences in event ratesbetween strategies shown in Tables 46 and 47 and Tables 48 and 49 are, in part, explained by differencesin the populations compared, i.e. lower event rates are in part achieved by positive tests removing those atrisk from the reported population rather than actually preventing adverse events.Tables 46 and 47 show that if patients are discharged without testing, their risk of death and non-fatalMI over the following year are estimated to be around 2.5% and 6%, respectively. We estimated that thevarious testing strategies could reduce these risks by 0.5–0.7% and 0.9–1.3%, respectively, in patientswithout known CAD and by marginally more in patients with known CAD.Tables 48 and 49 show that the various testing strategies reduce the estimated risk of adverse outcomeafter discharge with a negative assessment but, based on the Mills data, 155 the rate of death and non-fatalMI remained 1.0% and 3.9%, respectively, even after a negative 10-hour troponin result.Table 50 shows the results for the sensitivity analysis using high-sensitivity TnI instead of HsTnT atpresentation. Only the ICERs for presentation TnI and 10-hour troponin testing are shown becauseTABLE 46 Deaths and non-fatal MI at 1 year among patients presenting without known CAD following differenttesting strategies: whole population (n = 1000)Strategy MI DeathsMIs avoided comparedwith no testingLives saved comparedwith no testingNo testing 56.57 24.00 – –Presentation TnT, 10% CV 47.22 18.80 9.45 5.20Presentation TnT, 99th percentile 46.50 18.40 10.07 5.60Presentation HsTnT, 99thpercentile44.49 17.29 12.08 6.7110-hour troponin test 43.97 17.00 12.60 7.00TABLE 47 Deaths and non-fatal MI at 1 year among patients presenting with known CAD following different testingstrategies: whole population (n = 1000)Strategy MI DeathsMIs avoided comparedwith no testingLives saved comparedwith no testingNo testing 58.57 25.60 – –Presentation TnT, 10% CV 48.16 19.81 10.41 5.79Presentation TnT, 99th percentile 47.36 19.36 11.21 6.24Presentation HsTnT, 99thpercentile45.12 18.12 13.45 7.4810-hour troponin test 44.53 17.80 14.04 7.80© Queen’s Printer and Controller of HMSO 2013. This work was produced by Goodacre et al. under the terms of a commissioning contract issued by the Secretary of Statefor Health. This issue may be freely reproduced for the purposes of private research and study and extracts (or indeed, the full report) may be included in professional journalsprovided that suitable acknowledgement is made and the reproduction is not associated with any form of advertising. Applications for commercial reproduction should beaddressed to: NIHR Journals Library, National Institute for Health Research, Evaluation, Trials and Studies Coordinating Centre, Alpha House, University of Southampton SciencePark, Southampton SO16 7NS, UK.93